Javascript JSON mutli 按值和对象对行进行分组（嵌套）答案

【问题标题】：Javascript JSON mutli group rows by value and objects (nested)Javascript JSON mutli 按值和对象对行进行分组（嵌套）
【发布时间】：2018-03-05 11:41:50
【问题描述】：

我尝试了一段时间用 lodash .groupBy 转换我的数据

这是一个常见的情况：订单行有折扣（或没有折扣）

从这里

data = [  {"order":"O1","headerO1":"559518","lastUpdateDate":"2018-03-02T11:17:02.748Z","detailLines":{"linePosition":1,"item":"itemA","discounts":{"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.2}}},
    {"order":"O1","headerO1":"559518","lastUpdateDate":"2018-03-02T11:17:02.748Z","detailLines":{"linePosition":2,"item":"itemB","discounts":{"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.5}}},
    {"order":"O1","headerO1":"559518","lastUpdateDate":"2018-03-02T11:17:02.748Z","detailLines":{"linePosition":2,"item":"itemB","discounts":{"lineDiscountPosition":2,"discountReasonCode":12,"discountRate":0.5}}},
    {"order":"O1","headerO1":"559518","lastUpdateDate":"2018-03-02T11:17:02.748Z","detailLines":{"linePosition":3,"item":"itemD","discounts":{"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.4}}},
    {"order":"O2","headerO1":"660123","lastUpdateDate":"2018-03-04T23:23:00.000Z","detailLines":{"linePosition":1,"item":"itemA"}},
    {"order":"O2","headerO1":"660123","lastUpdateDate":"2018-03-04T23:23:00.000Z","detailLines":{"linePosition":2,"item":"itemD","discounts":{"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.4}}}
    ]

到这个结果

var data = [
{"order":"O1","headerO1":"559518","lastUpdateDate":"2018-03-02T11:17:02.748Z",
  "detailLines": [
    {"linePosition":1,"item":"itemA",
      "discounts":
        {"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.2}
    },
    {"linePosition":2,"item":"itemB",
      "discounts":[
        {"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.5},
        {"lineDiscountPosition":2,"discountReasonCode":12,"discountRate":0.5}
       ]
    },
    {"linePosition":3,"item":"itemD",
      "discounts":{"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.4}
    }
  ]
},
{"order":"O2","headerO1":"660123","lastUpdateDate":"2018-03-04T23:23:00.000Z",
  "detailLines": [
    {"linePosition":1,"item":"itemA"},
    {"linePosition":2,"item":"itemD",
      "discounts":
        {"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.4}
    }
  ]
}
]

它可以是 lodash、纯 javascript (node.js) 或其他库的解决方案。

到目前为止我尝试过：

var grouped = _.chain(data).sortBy('order.detailLines.linePosition')
    .groupBy('order.detailLines.linePosition'); 
console.log(JSON.stringify(grouped ,null,' '));

我想我可能需要一个关于 groupBy 的循环？

感谢您的帮助

【问题讨论】：

你能告诉我们你到目前为止做了什么吗？
var grouped = _.chain(data) .sortBy('order.detailLines.linePosition') .groupBy('order.detailLines.linePosition') ; console.log(JSON.stringify(grouped ,null,' '));也许需要一个 groupBy 循环？

标签： javascript node.js lodash

【解决方案1】：

想试试这个吗？请注意，reduce 是从右侧开始的，因为我在行项目之前添加了构造数组。

data = [  {"order":"O1","headerO1":"559518","lastUpdateDate":"2018-03-02T11:17:02.748Z","detailLines":{"linePosition":1,"item":"itemA","discounts":{"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.2}}},
    {"order":"O1","headerO1":"559518","lastUpdateDate":"2018-03-02T11:17:02.748Z","detailLines":{"linePosition":2,"item":"itemB","discounts":{"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.5}}},
    {"order":"O1","headerO1":"559518","lastUpdateDate":"2018-03-02T11:17:02.748Z","detailLines":{"linePosition":2,"item":"itemC","discounts":{"lineDiscountPosition":2,"discountReasonCode":12,"discountRate":0.5}}},
    {"order":"O1","headerO1":"559518","lastUpdateDate":"2018-03-02T11:17:02.748Z","detailLines":{"linePosition":3,"item":"itemD","discounts":{"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.4}}},
    {"order":"O2","headerO1":"660123","lastUpdateDate":"2018-03-04T23:23:00.000Z","detailLines":{"linePosition":1,"item":"itemA"}},
    {"order":"O2","headerO1":"660123","lastUpdateDate":"2018-03-04T23:23:00.000Z","detailLines":{"linePosition":2,"item":"itemD","discounts":{"lineDiscountPosition":1,"discountReasonCode":12,"discountRate":0.4}}}
    ]
    
console.log(
_.chain(data)
  .groupBy('order')
  .mapValues(details => ({
    ...details[0],
    detailLines: details.map(({ detailLines }) => detailLines)
  }))
  .values()
  .value()
)

&lt;script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js"&gt;&lt;/script&gt;

【讨论】：

很好的结果 Markus.For "order": "O1"."detailLines"，我们应该只有一个 "linePosition": 2 和一个由 2 个对象组成的数组 {"lineDiscountPosition"... } .还有一点，我在单元测试中的错误 "linePosition":2,"item":"itemB" 必须有项目（不是 "linePosition":2,"item":"itemC"）：将其修复到我的第一篇文章中跨度>
我简化了我的代码。您应该能够通过以嵌套方式添加相同的逻辑来对您的 linePositions 进行分组。